1. Field of Invention
This invention relates generally to applications that are declarative (passive) content, executable (active) content, or some combination of declarative and executable content. Specifically, a cascadable state machine for broadcast content that includes a collection of rules for how content objects that control other pieces of content would reflect their execution states is disclosed.
2. Description of Related Art
It is common to associate an execution state machine with both declarative (passive) content and executable (active) content. The concept applies to both broadcast content, interactive content, and Internet content. In the context of downloadable interoperable content, such as Java Byte Code, the javax.tv.xlet.Xlet interface provides the execution state machine for broadcast content while the java.applet.Applet class provides the execution state machine for Internet content. The state machines let the platform (as well as remote objects) observe and control the progress of content execution and understand its implications on resource allocation. The current practice is for a single piece of content to delegate either to standard (perhaps interoperable) platform packages or to download (perhaps interoperable) content specific packages that in turn delegate to platform packages.
Unfortunately, however, if the content delegates to a downloadable package to realize itself, it is difficult for the platform (or perhaps remote objects) to observe and control the delegate packages. It is also not obvious to the platform which content relates to which delegate packages, nor is it obvious whether the control (such as the deletion) of specific pieces of content affects the delegate package. It is also not clear to the platform whether the control (such as the deletion) of a delegate package affects specific pieces of content.
Therefore what is desired is a cascadable state machine for broadcast content.
According to the present invention, methods, apparatus, and systems are disclosed for providing a cascadable state machine for broadcast content is disclosed.
In one embodiment, a cascadable state machine that observes the execution state machine of multiple client applications, aggregates the multiple execution states into a single execution state for the observation object, reports the aggregate execution state through the same execution state machine interface as the client applications, and cascades changes to the execution state machine of the observation object to the client applications.
In another embodiment, a method for providing a cascadable state machine is disclosed that includes observing an execution state machine associated with a plurality of multiple client applications each having an associated execution state, aggregating the associated execution states into a single aggregated execution state suitable for an observation object, reporting the single aggregated execution state through the same execution state machine interface as the client applications, and cascading a change to the execution state machine of the observation object to the client applications.
In yet another embodiment, computer program product executable on a computing system arranged to provide a cascadable state machine in a computing system is disclosed that includes computer code for observing an execution state machine associated with a plurality of multiple client applications each having an associated execution state. Also included are computer code for aggregating the associated execution states into a single aggregated execution state suitable for an observation object, computer code for reporting the single aggregated execution state through the same execution state machine interface as the client applications, computer code for cascading a change to the execution state machine of the observation object to the client applications, and computer readable medium for storing the computer program product.